CLONING OF GENE ENCODING THE VISUAL PIGMENTS IN THE SILKWORM, BOMBYX-MORI

The polymerase chain reaction (PCR) was performed with cDNA from the s ilkworm compound eye and primers designed to amplify a region of the o psin-encoding cDNA. Two distinct fragments which encode two opsins, de signated Bomopsin1 and Bomopsin2, were isolated. The fragments of Bomo psin1 and 2 consisted for 207 nucleotides (nt) encoding a sequence of 69 amino acids (aa), and 213 nt encoding 71 aa, respectively. The dedu ced amino acid sequences of Bomopsin1 and 2 showed 100-68% identity an d 94-63% identity to the corresponding region of other insects opsin. the high identities between Bombyx and Manduca opsins suggest that Bom opsin1 is a green-sensitive pigment and Bomopsin2 is a UV-sensitive pi gment in the silkworm eye.